.mock-container {
  width: 100%;
  height: 100%;
}
.code-area .code__box {
  float: left;
  box-sizing: border-box;
  border: 5px solid transparent;
  width: 50%;
}
.render-box {
  box-sizing: border-box;
  border: 5px solid transparent;
}
.render-btn-list {
  border-bottom: 5px solid lightcoral;
  padding-left: 40px;
  padding-bottom: 5px;
}
.render-btn-list > button {
  margin-right: 10px;
}
.render-area {
  border: 5px solid transparent;
  min-height: 200px;
}
.render-area * {
  transition: .5s;
}